mirror of
https://github.com/hardkernel/linux.git
synced 2026-03-24 19:40:21 +09:00
defc914227
commitb90ecc0379upstream. Currently, associating a loop device with a different file descriptor does not increment its diskseq. This allows the following race condition: 1. Program X opens a loop device 2. Program X gets the diskseq of the loop device. 3. Program X associates a file with the loop device. 4. Program X passes the loop device major, minor, and diskseq to something. 5. Program X exits. 6. Program Y detaches the file from the loop device. 7. Program Y attaches a different file to the loop device. 8. The opener finally gets around to opening the loop device and checks that the diskseq is what it expects it to be. Even though the diskseq is the expected value, the result is that the opener is accessing the wrong file. From discussions with Christoph Hellwig, it appears that disk_force_media_change() was supposed to call inc_diskseq(), but in fact it does not. Adding a Fixes: tag to indicate this. Christoph's Reported-by is because he stated that disk_force_media_change() calls inc_diskseq(), which is what led me to discover that it should but does not. Reported-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Demi Marie Obenour <demi@invisiblethingslab.com> Fixes:e6138dc12d("block: add a helper to raise a media changed event") Cc: stable@vger.kernel.org # 5.15+ Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20230607170837.1559-1-demi@invisiblethingslab.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.